SanDisk Clip Go with SD Card inside

[Casper2021]

I just opened a SanDisk Clip Go because it was broken and I am curious,  only to find that there is a micro SD Card permanently mounted inside. I finally got it out, put it in my android,  reformatted it and it works.  So can anyone tell me if the firmware is stored on the SD card?

[speachy]

It is my understanding that the Clip Go executes firmware directly from the player's internal flash.  The SD card is only used for media storage, although I think that the Clip Go's firmware update process can operate from either.

(The SoC used in the newer Sansa Clips has very little RAM, so it is highly unlikely the firmware is loaded into RAM first)

[Casper2021]

Maybe I didn't say it correctly, the SD card IS the internal flash memory.  It is in a sd card reader that it mounted and the glued closed.  Have you ever seen a sd card INSIDE being used for internal storage?

[speachy]

I don't think I've ever seen an SoC capable of directly executing its firmware off the SD card without loading it into RAM first.

Given the lineage of the Clip Sport series, it's more likely that there is still some sort small flash chip onboard, solely used for firmware storage.. and with the SD card removed, I would expect the device to boot up. Since you have yours apart, can you post photos or other details about the various chips it has?  I've only found photos of older models in the series, not the Clip Sport Go.

Still, there is nearly no documentation to be had on this series of SoCs, and due to their severe resource constraints there hasn't been much interest in figuring out how to build or otherwise modify its firmware.  HEre is one of the few things I found:

  https://github.com/nfd/atj2127decrypt

[saratoga]

They make special solder able sd cards for this purpose, so including a slot is strange. Probably they had access to a lot of cheap cards.

On the other sandisk players the mask rom includes enough of a driver to initialize the external storage. Probably these work similarly.

[Casper2021]

So here is a picture of the Clip Go.  As you can see, there is an sd card reader directly in the middle if the board. The processor is a ATJ 2167 but the only onboard memory I see is the SD Card.

[Casper2021]

If I had to guess, they designed it to swap out the 8gb, 16gb and 32gb cards.  So when I pylled the card out and put it in my phone it forced me to format it to use it, but the card certainly works.

[saratoga]

What's the text on the CPU? ATJxxxx ?

[Casper2021]

ATJ 2167